RESUMO
UNLABELLED: The Streptokinase (SK) regimen (1.5 MU/60 minutes) has remained unchanged for the past 20 years in patients with ST-segment elevation acute myocardial infarction (STEMI) due to fear of hypotension (a specific effect of this thrombolytic agent) and of hemorrhagic complications. OBJECTIVE: To evaluate the influence of the Streptokinase-induced hypotension (SK-hTA) on the rate of coronary reperfusion (CR), incidence of cardiogenic shock (CS), 30-day mortality and incidence of stroke in patients (pts.) with STEMI. The SK-hTA was defined as decrease of the systolic blood pressure with at least 20% within the first 20 min. after the start of the SK infusion. METHODS: A group of 837 pts. (age 20-90) with thrombolytic treatment, with three "accelerated" SK regimens within the first 6 hours after the onset of STEMI and enrolled in the Romanian open, prospective, non-randomised study for accelerated SK in STEMI (ASK-ROMANIA) have been included. The SK regimens consisted in infusing of the standard dose of 1.5 M.U. either in 30 min. (regimen SK1.5/30, 173 pts).) or in 20 min. (regimen SK1.5/20, 377 pts.) or of the half dose (0.75 M.U.) in 10 min. followed by a new infusion of 0.75 M.U. after 50 min. only if no bed-side signs of CR have been recorded (regimen SK 0.75/10, 287 pts.). The speed of the SK infusion was maintained in all pts. experiencing SK-hTA. All pts. received aspirin and heparin or enoxaparin if not contraindicated. Three noninvasive CR criteria have been used: 1. Rapid cessation of the chest pain. 2. Rapid decrease of the ST segment elevation by more than 50% of the initial value. 3. Rapid increase of the CK and CK-MB with a peak within the first 12 hrs. RESULTS: SK-hTA appeared in 372 pts. (44.55%) at 9+/-5 min after the start of the SK infusion. In this subgroup the rate of CR was 74.46%, non-significantly higher than the one of 68.81% registered in pts. without SK-hTA (p=0.071). SK-hTA disappeared in all patients after 16+/-6 minutes without a specific therapy. Fourteen pts. with SK-hTA (3.76%) and 16 pts. without SK-hTA (3.44%) developed CS after thrombolysis ( non-significant difference). The global in-hospital mortality was 10.21% in pts. with SK-hTA and 9.89% in pts. without this side effect (non-significant difference). The incidences of hemorrhagic and ischemic strokes were 0.26% (1 patient) respectively 0.52% (2 pts.) in the SK-hTA subgroup and 0.43% (2 pts.) respectively 0.64% (3 pts.) in the subgroup without SK-hTA. CONCLUSIONS: 1. Despite a very high incidence (44.55%) the SK-hTA has not a detrimental effect in pts. treated with accelerated SK regimens for STEMI. 2. Streptokinase can be rapidly administered without an increased risk.